I just wanted to ask where you’ve heard of Vitamin D overdosing? I’ve only heard of it in levels near the millions of IU. From everything I’ve read (from the Vitamin D Council, included) 50,000IU is acceptable each day. I’m not saying that you’re incorrect, because I have heard of problems with calcium for those who take extreme amounts (100k’s IU ranges, but not anything below several 100K), so I am just trying to get more information. I have looked up on the NIH and CDC websites, and not yet found any information on what exactly constitues a vitamin D overdose, but it is something that has been on my mind. I’ll look more into the blood level, I do want to get tested. Thank you again for all of your help.
One quote I found:
“The lack of adverse effects in clinical trials that used intake up to 1250 micrograms [50,000 IU] vitamin D per day and the lack of adverse effects at lower doses inspires a high level of confidence in the data from the strongly designed clinical trials that used 250 micrograms [10,000 IU] vitamin D per day,” said the reviewers.
The researchers also note that for practically all the reported cases of vitamin D toxicity have involved doses that were in excess of those studied in the clinical trials. “Newer clinical trial data are sufficient to show that vitamin D is not toxic at intakes much higher than previously considered unsafe,” said the reviewers.”
-J.N. Hathcock, A. Shao, R. Vieth, R. Heaney. Risk assessment for vitamin D. American Journal of Clinical Nutrition; January 2007, Volume 85, Pages 6-18.
http://www.rejuvenation-science.com/n_vitamin-d-upper-limit.html
Dr. Cannell published the following letter from a reader, along with his response, in an email I received 4/21/10. It should answer your question:
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Dear Dr. Cannell:
I was taking a vitamin D3 liquid oil supplement 60,000 IUs/day regularly and 180,000 IUs/day fairly occasionally for about 8 months in ‘09 in an attempt to get over a chronic sinus infection and prevent cold/flu. Last November ‘09, I started having symptoms for irregular heartbeats, nervousness, insomnia, weight loss, difficulty concentrating, and muscle weakness. I met with my physician and had blood work done. My vitamin D3 level was 406 ng/mL and my calcium elevated and probably had been that high for several months. I stopped taking the supplement immediately. But my physician didn’t recommend anything else at the time except to recheck the blood levels in a few months. I am 46 and have been in excellent health all my life with no previous medical issues.
The symptoms have not gone away entirely. I was not aware of the potential toxic effects of D until a few weeks ago. I recently found out that vitamin D toxicity can cause hypercalcemia.
Is there anything more I can do now to reverse the effects of vitamin D toxicity and possible hypercalcemia that may have been present for several months last summer/fall? Should I have my kidney function and heart function checked? What can I do to reverse effects on my nervous system and brain now? What tests can I do to keep checking the levels or know if I did any permanent damage to these soft tissues?
Finally, my daughter (5 yrs. old at the time) was also taking about 20,000 IUs/day fairly regularly over the same period of time. She didn’t appear to have had any adverse symptoms but now I’m really concerned and scared she may have been toxic too. What tests should I ask to be done to check her for Vitamin D toxicity and hypercalcemia?
Thank you,
David, Utah
Dr. Cannell’s Response was:
Dear David:
Congratulations, you have indeed made yourself toxic by knowingly taking too much supplemental vitamin D, one of the first such cases I am aware of in the modern literature. Have your daughter’s 25(OH)D and serum calcium checked; she was also taking potentially toxic doses.
The treatment for you and your daughter to not take any vitamin D and both of you should stay out of the sun until your 25(OH)D levels return to normal. Drink 8 eight-ounce glasses of water a day and have your daughter drink four. You both should have a chemistry panel periodically to see if kidney function is normal and to check serum calcium although I doubt that your calcium is still elevated. I doubt you have permanently damaged any internal organs as most cases of toxicity, with 25(OH)D levels higher than yours, did not result in permanent damage to the kidneys or other internal organs.
Also, readers should be aware, if they are not already, that vitamin D does not prevent all viral respiratory infections. As we noted in correspondence to our first influenza paper, rhinoviruses, the most common cause of the common cold, are not seasonal; that is, they are just as common in the summer as in the winter, and they do not have a lipoprotein coat for antimicrobial peptides to destroy. Also, in a recent Japanese paper, influenza B was not prevented by vitamin D, only influenza A. Although many people get influenza symptoms and are worried enough to go to their doctors, and their doctors worried enough to get an influenza A test, only about 3% of the specimens submitted to CDC surveillance centers are positive for influenza A.
If you are already taking 5,000 IU a day and you get a cold, chances are that more vitamin D will not help much. No one should take large doses for more than a few days and then only if the infection is severe. Certainly the doses you took were toxic and it sounds as if you still suffered from viral respiratory infections.
>>I just wanted to ask where you’ve heard of Vitamin D overdosing?<<
My post above was a response to your question. 50,000 IU per day will put you in the category of David in the letter. You will get sick. The confusion possibly arises because doctors will often prescribe a megadose (50,000 IU doses) to be taken once a month to overcome a dangerously low vit D3 level.
The reason so little has been actively researched regarding vit D3 is that until recently the Food and Nutrition Board had set the Tolerable Upper Limit at 2,000 IU per day. This level is too low to get the research results suggested by the associative studies. That is, to do an actual experiment, researchers would have to put people on doses significantly larger than the government’s upper limit. Reputable researchers are reluctant to do that.
However, recently the Tolerable Upper Limit was doubled to 4,000 IU, so you’re going to start seeing some experiments (double blind, placebo controlled) being done, I would expect.
Dr. Cannell, and most researchers, recommend around 1,000 IU’s daily per 30 pounds of body weight, PLUS regular testing to see how you’re responding to that dosage when combined with your lifestyle, diet, etc. Thus, a 180 pound person should be taking around 6,000 IU to maintain a high enough D3 level to be effective. (Checked by testing.)
As for the level, the most commonsense suggestion I’ve heard for setting a minimum level is from the doctor (I forget his name) who says that it doesn’t pass to the baby in breast milk until the mother’s blood is over 50 ng/ml. He reasons that since it is highly beneficial to the developing fetus, and to the new borne baby, the minimum should be above that level. Most of the researchers in vit D3 are settling on a level somewhere between 60-80 ng/ml and none that I’m aware of are stating a level above 100 ng/ml. Above 200 ng/ml, you’re likely to start getting in serious trouble.
Note: I am not a doctor, and the above is just being passed along, possibly with some errors. Do your own research before doing any supplementing. Kidney and Liver specialists will tell you that a large percentage of their patients come to them with long lists of supplements they’ve been taking. A lot of this stuff just isn’t good for you, but we’ve gone the wrong direction for 40 years when it comes to vit D3, in my personal opinion.